<?php
//获取文件后缀

//方法1：
function getExt1($filename)
{
   $arr = explode('.',$filename);
   return array_pop($arr);;
}

//方法2：
function getExt2($filename)
{
   $ext = strrchr($filename,'.');
   return $ext;
}

//方法3：
function getExt3($filename)
{
   $pos = strrpos($filename, '.');
   $ext = substr($filename, $pos);
   return $ext;
}

//方法4：
function getExt4($filename)
{
   $arr = pathinfo($filename);
   $ext = $arr['extension'];
   return $ext;
}


//方法5：
function getExt5($filename)
{
   $str = strrev($filename);
   return strrev(strchr($str,'.',true));
}


function getExtension($filename){ 
  $myext = substr($filename, strrpos($filename, '.')); 
  return str_replace('.','',$myext); 
}